News Release

Researchers Compile Most Detailed Map of an Underwater Eruption

Examining more than 50,000 seafloor images, geologists have
created the most detailed map ever assembled for a volcanic eruption along a
fast-spreading mid-ocean ridge. Researchers from the Woods Hole Oceanographic
Institution, University of Florida, and University of Hawaii
mapped where fresh new lava had paved over sediment-covered seafloor, while
also identifying eruptive fissures and channels where lava had flowed.
Scientists’ understanding of deep ocean volcanic eruptions has been limited by
the ability to observe them. In April 2006, researchers got an unprecedented opportunity to investigate the
dynamics of eruptions after discovering a recent lava flow along the East Pacific Rise (EPR) between 9° 46’ N and 9° 56’ N (900
km southwest of Acapulco, Mexico). Lead author Adam Soule and
colleagues used support from the National Science Foundation’s RIDGE2000
program to conduct 37 surveys of the site with WHOI’s digital deep-sea towed
camera system, plus another 10 dives in the submersible Alvin.
In analyzing the imagery, they identified 186 sites where new lava met old. They documented
that the eruption covered an area of 14.6 square kilometers with lava averaging
1.5 meters deep. More than 22 x 106 meters of lava were estimated to
flow out of the Earth, yet it was only about 15 percent of what was stored in
the magma chamber below the surface. The team observed that areas with the largest
lava output coincided with the greatest
concentrations of previously known hydrothermal vents. The map and
findings were published online on November 26, with a printed version coming in
the December issue of the journal Geology.